The proposed studies are designed to systematically examine auditory and visual attention in children with specific language impairment (SLI) using behavioral and event related potential (ERP) measures and to test the hypothesis that auditory attention is selectively impacted in SLI. This modality specificity of the attention dysfunction in SLI will be assessed relative to two groups of children who are expected to evidence less variation in performance on attention tasks across the two modalities. One control group will be children with attention deficit hyperactivity disorder (ADHD), a disorder associated with significant disruption of attention, and the other will be non- impaired children with normal language and attention. Demonstrating a modality difference in attention skills in SLI would 1) suggest that the attention difficulties in SLI children can be qualitatively different from those seen in ADHD and consequently, might require different forms of intervention, especially with regards to medication, 2) raise the speculation that early measures of auditory attention might be useful in predicting which children would evidence difficulties with language acquisition, 3) strongly argue for the use of visual aids in language intervention, and 4) highlight the role of auditory attention in normal language acquisition.